Accomplish the indicated achievement to get the corresponding number of Gamerscore points:

If I Had a Hammer (5 points): Build a lumbermill (Single Player).
Siegfried (or Roy) (5 points): Train a Kefling (Single Player).
Frank Lloyd (25 points): Unlock 25 blueprints (Single Player).
Big Bully (15 points): Became the big bully of the village (Single Player).
Haberdasher (20 points): Encounter every possible Kefling hat (Single Player).
Like Rabbits (15 points): Reach a total Kefling population of 30 (Single Player).
Think Big (10 points): Build a building made of more than 8 pieces (Single Player).
Master Builder (25 points): Build a cathedral (Single Player).
King (40 points): Finish a complete castle with three connected parts (Single Player).
Friend (10 points): Collect 10 unique player banners from other giants during Xbox LIVE play.
World Traveler (10 points): Play in an online game where 20 different player banners appear.
Vanity (20 points): Built a glorious statue of oneself (Single Player).